Ok--I'll just alter the drivers meeting--'If a working is waving GREY flag-stop. Go thru 2 grey flags you go home." I've stopped for workers waving a cloth cover stick (i.e. rolled up flag) and just waving their arms. If you see a worker doing something-stop. Its worked for 50 years. Its not the color-its the motion.

Translating road racing to hillclimbing:Proper tire selection== nothing hooks up on moss or wet leaves.Staying on the racing line==anything paved is considered good.

Just as a follow-up, in case another colorblind rookie has the same concern, this season was fine.

I was flagged several times, for various things from timing missing my start to an off further up the hill. None were an issue. It's hard to miss a human-shaped object trying to get your attention in the middle of a run up the hill.